Yes but the point I was trying to make is so what?

So it can only go as low as zero. So what if your metal is warped down slightly at (minus) -0.5mm at any particular point and your THC is cutting just fine? You just trashed the point of having THC because you stopped it following down to -0.5.

Alternatively what if your metal is at +0.5mm at any given point because it's warped up and you DO get a dive for some reason? you just crashed BEFORE you got to Zmin so it saved you nothing.

Which is why I asked you for a value you could put in Zmin that would do something useful 

Having just got the thing running, I now see what happens or at least can happen. I am deliberately cutting with the metal tilted so I can see what goes on, if it started at a high point and couldn't go lower then yes - fail.

I now have -3 min and 5 max, but i think more would be ok although a warpage of 5 to -3 is a pretty bent plate

Trying to get it dialled in now, getting top dross at present but at least its running and not crashing the torch or winding it way up high (any more )

I think I can see what it needs now.


What sort of values of hysteresis do others use, I'm not sure of the relationship between a volt or two and distance in the arc.
Currently set for +/- 4v

I now have -3 min and 5 max, but i think more would be ok although a warpage of 5 to -3 is a pretty bent plate

Not sure how else to say it really...

What sort of values of hysteresis do others use, I'm not sure of the relationship between a volt or two and distance in the arc.
Currently set for +/- 4v

Rule of thumb? I think it was Hypertherm who told me that in conventional plasma a volt is roughly 0.1mm - never checked it though - it kept melting my ruler.

Lol 

One good thing I do have going is a dual-purpose z height probe, first position is probe height, 3mm more is a limit switch so if it did ram the torch, the most that could happen is an e-stop

I have a lot to learn methinks, at least it's all playing nicely together now, the hypertherm was a revelation and solved a massive amount of grief with HF issues.

The hard part is learning blind, it would be so much easier to just have someone there to say "do this" or "do that" etc, that is why I have so many odd questions

the hypertherm was a revelation and solved a massive amount of grief with HF issues.

You have a Hypertherm? So I've spent my time helping you with a competitors THC. Serves me right for not checking I guess. Personally I blame Hood 

I started out with a HF pilot arc setup but it was wreaking havoc with the electronics that I could not surpass so in the end I blew the budget on a Hypertherm powermax 30xp, it's a hand system but all I (only just) afford and with my intermittent proposed usage, seems to fit the task well.

I have just fitted a Proma THC as it really was all I could afford.

Hopefully that's not an issue?

Quote from: Davek0974 on April 09, 2014, 02:18:21 PM

the hypertherm was a revelation and solved a massive amount of grief with HF issues.

Serves me right for not checking I guess. Personally I blame Hood 

Not my fault you are a bit slow on telling people of your product
Why not do as Jeff Birt does and have a link to your product every time you post. I cant see that being a problem as your product (as far as I know) is complementary to Mach rather than competition

Hood

So what IS this product then??

So what IS this product then??

http://www.razordance.co.uk/THC.htm

Hood

Quote from: Davek0974 on April 10, 2014, 03:42:14 AM

So what IS this product then??

http://www.razordance.co.uk/THC.htm

Hood

Ah, now I see, won't work for me though as my Powermax 30xp is a hand system and does not have the interface connector, the Proma uses the full arc voltage as reference.